Ford's 2013 hybrids aren't living up to their EPA fuel efficiency ratings. According to Consumer Reports, The 2013 Ford Fusion Hybrid and Ford C-Max 'have the largest discrepancy between our overall-mpg results and the estimates published by the EPA that we've seen among any current models.'

As the magazine's post says, "These two vehicles have the largest discrepancy between our overall-mpg results and the estimates published by the EPA that we've seen among any current models."

That's a pretty damning statement.

Consumer Reports goes on to note that the test results are fully 20 percent lower than the EPA rating, while, "Our overall-mpg results are usually pretty close to the EPA's combined-mpg estimate."

The post containing the comments includes a chart of the differences between CR's test results and the EPA ratings for 18 different cars it has tested recently. The two Ford hybrids top the list with the greatest difference.

At the other end are the 2013 Chevrolet Malibu Eco, which equaled its 29-mpg rating exactly, and the Honda CR-Z hybrid hatchback, in which CR's test drivers actually bettered its combined 34-mpg rating by 1 mpg.

(We would have preferred Consumer Reports to rank the differences by percent, rather than by the non-linear MPG scale, but the Fords would still have been at the top.)

Other outlets have reported similar results.AutoGuide, for instance, achieved just 40 mpg in a brief test of a Fusion Hybrid.

In those cases, the carmakers had to re-rate their cars; apologize profusely to the public, to officials, and to their buyers; and issue refunds to buyers of the affected cars for the increased gasoline costs over the cars' lifetimes.

Will Ford be forced to take similar action? Stay tuned; there's clearly more to come on this story.

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